Fabrication and characterization of photonic crystal cavities in the visible

We report on the fabrication and optical characterization of photonic crystal cavities for visible wavelengths made from silicon nitride (SiN). We note significant improvements in fabrication process with respect to our previous studies. The intrinsic luminescence of the SiN membranes was used as an internal light source to study the quality factor of the cavity modes. We experimentally found values as high as 3400, which are up to the present unsurpassed for photonic crystal resonators in the visible spectra range. Finite difference time domain (FDTD) simulations suggest another boost by a factor of two is possible by further optimizing the fabrication process. We describe a method by which arbitrary emitters or other nanoscopic objects can be coupled in a deterministic way by using the manipulation capabilities of an atomic force microscope.